This invention relates to an electrical connector for press fitting into a printed circuit board, an insulator block to accommodate several of these connectors and a jig to connect an assembly of the connectors and insulator block to a printed circuit board.
Where it is desired to have a large number of connections to a printed circuit board, there are generally provided a number of elongated electrical connectors. Each of the connectors is assembled to a portion of the printed circuit to attain an electrical connection and a mechanical connection between the printed circuit board and each connector. This connection is often obtained by way of spring characteristics of that portion of the connector inserted into a hole of the printed circuit board. The connector is forced into a hole in the board to retain a fixed mechanical connection. Often a wire is used to obtain the electrical connection; however, this is not always used. In such an arrangement, inspection of the connectors and insulator blocks must be done separately for each of these components at the time of shipping and after receipt thereof. This involves a number of complicated procedures for inspection. When considered from the viewpoint of quality control of the total electrical connector assembly substantial effort is required. The individual connectors and insulator blocks are separately supplied. The user must then assemble these components. Due especially to the small size of the connectors, many problems are experienced. There are problems in assuring quality of the assembly, such as a problem of maintaining the connectors in an accurately aligned condition during assembly to the printed circuit board. Further, there is additional work on the part of the user to assemble the connectors to the insulator. This is a tedious task. If a jig or tool is required to assemble the connectors, the jig itself is quite complicated in structure to attain a high degree of assembly precision. Consequently, the jig to assemble connectors into the insulator block or socket is expensive. The present invention provides an electrical connector and block assembly and a jig for mounting the assembly on a printed circuit board that solve these problems.
In accordance with the present invention, there is provided an electrical connector for press fitting into a printed circuit board. The connector is stamped from a sheet metal blank having spring characteristics into an elongated and narrow structure. The generally middle part of the connector is formed into a rectangular shape. A spring portion is provided below the rectangular portion and a bar shaped portion for connection to a printed circuit board extends downwardly from below the spring portion. A strip shaped upper half of the connector above the rectangular portion is the part of the connector which is retained within the insulator block. The strip portion immediately above the rectangular portion has a curvature of small radius, followed by an inclined portion from which there extends a curved portion of large radius to form a contact portion of the connector.
The substantially central area of the intermediate rectangular portion of the electrical connector described above is blanked to form an insertion hole of polygonal, circular or oval shape. A claw of a jig constructed in accordance with another aspect of the present invention and described later enters into this hole to ensure that force used to insert the end of the connector into a printed circuit board is applied to the connector at the middle of the connector and along the axis of the bar shaped end portion of the connector. On one side of the intermediate rectangular portion, at an upper centrally located portion thereof, there is formed a protrusion having a sharp edge which cuts into the plastic body of the receiving insulator block to hold the connector firmly in the block.
Below the intermediate rectangular portion of the connector, and by way of a constricted portion, there is provided a spring portion having a lateral width slightly smaller than that of the intermediate rectangular portion, and a circular or oval hole may be formed centrally of the spring portion to allow spring gripping with the printed circuit board.
The connector as defined above can be forced into a channel or slot in the insulator block with the intermediate rectangular portion performing different functions. This portion is flat and coacts with a plane surface in the block to orientate the connector with respect to the block. Upper, transversely spaced shoulders on this portion, which is larger than the end of the connector located in the upper socket area of the block, abut the inward ends of spaced grooves in the mounting slot for a connector in the block. This abutting action locates the connector axially in the block and the two spaced shoulders stabilize the vertical alignment of the extending end of the connector. By providing a sharp edge to cut into the insulator block when the connector is forced into a receiving slot of the block, the connector is prevented from inadvertent withdrawal from the block. When several connectors are so secured, the block is held firmly on the printed circuit board by the interaction of all connectors with the block.
In accordance with an aspect of the invention, the connectors are provided with aligning and assembly openings which are preferably in the flat intermediate boss or plate. By inserting interconnected claws of a jig into these openings through clearance openings in the side or sides of the insulator block, the connectors are fixedly aligned by claws and the connectors can be driven into apertures on the printed circuit boards by forcing the claws toward the board. The extended ends are aligned with the intermediate portion so that the insertion force is in a straight line along the longitudinal axes of all outwardly extending ends of the respective connectors.
The present invention further includes an insulator body or socket which has slots to accomodate two generally parallel rows of connectors of the kind described above. Such insulator socket is formed as a block which is elongated in its lateral direction and has sufficient thickness or width to support pairs of transversely spaced connectors. A lateral groove is formed centrally of the insulator block. The depth of this groove is slightly greater than one half the height of the block and the upper portion of this groove is open outwardly and upwardly to define a socket area for subsequent connection of a contact head. A triangular cross sectioned guide portion is positioned below the opened groove. A series of partition walls with a given distance therebetween are located internally of the insulator block to define slots for accepting the several connectors and separating the upper contact portions of the connectors. At the lower end of the partition walls, there are provided a vertical groove for receiving a shoulder of the intermediate rectangular portion of a connector and a connector retaining portion. A guide of an inverted triangular shape is provided to facilitate insertion of the connector and to securely retain the connector in the insulator block. A series of slots or side openings are formed at lower portions on both sides of the block for insertion of the claws of a fitting jig to engage and align connectors in said block. The insulator block just described may be made of insulating plastic material in one piece.
This invention further provides a jig for mounting to a printed circuit board an assembly formed by inserting the above described connectors into the insulator block just explained. This jig is made of a metal material and has a pair of end walls connected by a central wall. A pair of fitting walls are mounted onto the opposite sides of the central wall at a suitable distance. A series of claws projecting from these fitting walls toward the central wall are provided at the lower portion of each fitting wall. The end portion of each claw is appropriately shaped to match the shape of an insertion hole of a connector. The upper part of the fitting wall is connected to the central wall by means of springs, with a pivotal mounting projection of the central wall fitting into a recess of the fitting wall. The parts of the fitting jig are so designed that as upper portions of the fitting walls are pressed toward each other, the lower portions of the fitting walls open. The claws can be inserted into slots or side openings of the insulator block. When the force applied to the upper portions of the fitting wall is released, the claws move through the slots or side openings of the block and then enter into the insertion holes of the intermediate rectangular portions of the individual connectors. Since the lower portions of the end walls are connected to two low base elements by springs, the connector assembly held by the jig can be attached to the printed circuit board by pressing the movable portion of the fitting jig and the assembly carried by the claws of the fitting walls on the movable portion toward the printed circuit board. When the assembly is attached to the board, the upper portions of the fitting walls are pressed together to release the claws from the assembly. Then the jig is removed.
The primary object of the present invention is to provide an elongated printed circuit board type connector, an insulating socket block for receiving several of the connectors and a jig or tool for attaching the socket block and connectors onto a printed circuit board, which components are easy to assemble and use, provide aligned connectors for presentation to the board, and exert attaching forces only through the elongated connectors.
Another object of the present invention is the provision of an elongated connector, socket block and tool as defined above, which components employ an opening in the connector for engagement with an element on the tool for applying an attaching force between the tool and connector after the connector is assembled onto the socket block.
Still a further object of the present invention is the provision of components as defined above, which components reduce the effort in assembling connectors or socket blocks and in attaching the connectors onto a printed circuit board.
These and other objects and advantages will become apparent after consideration of this disclosure which includes the accompanying drawings: